The 400G QSFP-DD ZR+ is designed to 100G/200G long haul and 300G/400G Metro IP over DWDM applications without inline chromatic dispersion compensation. 400G DP-16QAM modulation format. With one VOA inside the TX optical path the out output optical power has 4dB attenuation window. ZR+, Standard Tx output power (-10dBm), C-band tunable, Pull tab, 0°C to 70°C, LC receptacle The emerging OIF 400ZR and Open ZR+ MSA coherent transceivers in QSFP-DD and OSFP form factors generally have low transmit output power (-10 dBm), making them incompatible with ROADM networks. Consequently. Cisco QSFP-DD and OSFP 800G ZR/ZR+ digital coherent optics modules enable 800G traffic over amplified Dense Wavelength-Division Multiplexing (DWDM) links up to 120 km for 800ZR and over 1000 km for 800G ZR+. In recent times, the advent of 400G DWDM coherent pluggable optical modules has spurred the development of coherent DWDM. Cisco offers a range of GBIC, SFP, XFP, SFP+, CXP, CFP, Cisco CPAK, and QSFP+ pluggable modules. These small, modular optical interface transceivers offer a convenient and cost-effective solution for an array of applications in the data center, campus, metropolitan-area access and ring network.